1. Field of the Invention
The present invention relates generally to an apparatus and method for covering a chair form with fabric and it relates, more particularly, to an apparatus and method for securing fabric to a chair form in a manner which stretches the fabric uniformly over the form in order to control the shape of the upholstery and to prevent limpness of portions of the fabric at edges of the form.
2. Description of the Prior Art
In the manufacture of fabric covered chairs and other furniture, a process is known for securing a fabric piece to a form, such as a seat or back member, by sewing an overcast stitch at the border of the fabric piece and trapping a drawstring within a passageway formed thereby. The fabric then can be placed over the front of the form, stretched over the edges of the form and drawn tight by the draw string at the back of the form such that the fabric completely covers the form edges. Such a process is disclosed in U.S. Pat. No. 4,732,097 issued to Guilhem on Mar. 22, 1988, which is incorporated herein by reference.
When using a fabric having a draw string along its border to cover a form, the string applies greater force to the fabric at sharp curves or corners of the form tending to pull the fabric more tautly at the curves or corners. Most chair forms, such as seats and backs, are non-circular in shape and are often generally rectangular with sharply bent or curved corners. Thus, when drawn over the edges of the form, the fabric is applied relatively tightly at the corners and is relatively limp along the straight or less curved edges of the form. The result is a covered form wherein the fabric puckers or puffs out along the straight or less curved edges of the form, creating an unacceptable finished product.
In order to provide adequate control of upholstery shape and to solve the problem of limpness along the straight or less curved edges of the form, it has been previously necessary to manually pull the upholstery fabric inwardly of the form at the puckered or puffed sections until the fabric becomes tight and then to staple or otherwise affix the fabric to the back of the form. In an alternative approach which has been previously employed, the form is provided with a series of hooks which are fastened to the back of the form and are positioned so that the draw string can be pulled inwardly of the form into engagement with the hooks. However, it is to be noted that both of these methods require additional labor in the assembly of a fabric covered forth. Also, it has been found that the use of staples or hooks placed intermittently along the back of the form causes the fabric to assume a scalloped configuration at the adjacent edge intermediate the fastening points. This, results in an upholstered product having a covering exhibiting an unacceptable appearance.
It would, therefore, be desirable to provide an apparatus and method for enabling control of the upholstery shape and for pulling the fabric of a covered form over the edges of the form in a uniformly tight manner whether the form has a circular or non-circular shape.